4. Caffeine
• Caffeine is most widely consumed CNS
stimulant.
• A cup of instant coffee or strong tea
contains 50-70mg of caffeine
• Average daily consumption is about
200mg, in tea & coffee drinking countries
• Nuts of cola plant also contain caffeine
• CNS stimulation & Diuresis are its
pharmacological actions
• Main psychological effects are remove
5. Mode of action
• Antagonize adenosine receptors
• Activates nor-adrenaline neurons
• Effect the local release of dopamine &
glutamate
6. Effects on different body
function
• CVS: produce positive ionotrpic and
chronotropic effects on heart.
• GIT: increase gastric secretions, therefore
should be avoided in peptic or gastric
ulcer
• Urinary system: produce mild diuretic
action & increase urinary output of
elctrolytes.
7. Clinical uses
• Caffeine relax the smooth muscle of
bronchioles therefore effective in asthma
• It is included with aspirin or paracetamol in
some preparations to treat headaches or
other aches
8. Nicotine
• Nicotine is named after the tobacco plant
Nicotiana tabacuma which acts as a
nicotinic acetylcholine receptor agonist.
• Average 1 cigarette yields about 1 mg
nicotine. As nicotine enters body it quickly
distributed throughout blood stream and
crosses BBB reaching brain within 10-20
seconds after inhalation.
• Eliminatin half life is 2 hrs
9. • Metabolized in liver by cytochrome P450
enzyme system mostly by CY2A6 &
CY2B6
• Major metabolite is cotinine
10. • By binding to nicotinic acetylcholine
receptors, it increases the level of several
neurotransmitters in the brain.
• Tobacco smoke contains monamine
oxidase inhibitors.
• Powerful interaction between MAOs and
Nicotine are responsible for addictive
effects of smoking
11. Withdrawal
• Nicotine withdrawal is mild as compared to
opiods and involves irritability with
insomnia .
• Nicotine is among the most addictive
drugs and relapse after attempted
cessation is common
12. Treatment
• Antidepressant BUPROPION is approved
for nicotinic cessation therapy .
• It is most effective when combined with
behavioral therapies
13. Amphetamines
• Amphetamines are group of synthetic,
indirect acting sympathomi metic drugs
that cause the release of endogenous
biogenic amines such as dopamine and
noradrenaline.
14. Mechanism of action
• It stimulate both alpha & beta
adrenoreceptors through an indirect
mechanism(by release of intracellular
catecholamines and MAOs blockade)
15. Pharmacological effects
• CNS: Psychic stimulation resulting in
feeling of euphoria, self confidence,
wakefulness, alertness with increase
mental and physical activities.
• It has anti-fatigue & analeptic action
• It has mild analgesic properties, also
increase analgesic effect of opiod and
decrease effect of nitric oxide
16. • It depress appetite by central action on
hypothalamus feeding centers by
reduction sense of smell and taste
• Chronic abuse leads to psychotic state
with delusion and paranoia like
schizophrenia.
• CVS: increase BP and reflex bradycardia
with large doses may cause arythmias
17. Clinical uses
Narcolepsy (its derivative methylphenidate
is more better).
Hyperkinetic syndrome(attention deficit
disorder)
Nocturnal enuresis
As nasal decongestant
19. Cocaine
• Cocaine is alkaloid found in the leaves of
Erythroxylon coca.
• A shrub endogenous to the Andes.
• For more than 100 years it has been used
in clinical medicine as a local anesthetic
agent and to dilate the pupil in
ophthalmology.
20. Mechanism of action
• In CNS cocaine blocks the uptake of
dopamine, noradrenaline, and serotonin
through their respective transporters.
• The block of dopamine transporter by
increasing dopamine concentration in the
nucleolus accubens has been indicated in
reward effect of cocaine.
21. Adverse effects
• Loss of appetite
• Hyperactivity
• Intracranial hemorrhage
• Ischemic stroke
• Myocardial infarction
• Seizure
• Hyperthermia, coma &death on high
doses
22. HALLUCINOGENS
Hallucination: is a sense or perception(sight,
touch, smell, sound or taste) that has no
basis of external stimulation.
Hallucinogens are characterized as agents
which produce hallucinations
23. Cannabinoids
• 1)Endogenous cannabinoids: these
• include 2-arachidonyl (2-AG) &
anandamide, both bind to CB1 receptors
where they inhibit release of either
Glutamate or GABA receptors.
• Due to this backward signaling they are
called retrograde Messengers'
24. • Exogenous cannabinoids:
• These include Marijuna and other
pharmacological active substances like
Tetrahydrocannabinol (THC)
25. Tetrahydrocannabinol (THC)
• This is a powerful psychoactive substance
like opiods
• Causes release of Dopamine neurons
mainly by pre-synaptic inhibition of GABA
neuron in the VTA
• Half life of THC is about 4 hrs
• The onset of effect of THC after smoking
marijuna occur within minute
26. • The prominent effects are euphoria,
relaxation , feelings of well being,
grandiosity and altered perception of
passage of time
• Dose dependant perceptual
changes(vision distortion)
• Drowsiness, diminished coordination and
memory impairment may occur
27. • Rarely Cannabinoids create dysphoric
state with higher doses
• Hashish ------ produce visional
hallucination, depersonalization and frank
psychotic episodes
• Increase appetite, nausea, decrease
intraocular pressure and relief of chronic
pain
28. • Chronic use of marijuna produce
dependency with mild withdrawal
symptoms, like restlessness, irritability,
mild agitation and insomnia.
29. Lysergic acid diethylamide(LSD)
• Multiple sites in CNS are affected by LSD
• It shows agonistic activity at presynaptic
5HTI receptors in the midbrain and
stimulates 5H2 receptors
30. Physical effects
• LSD can cause pupil dilatation
• Reduce or increase appetite
• Increased wakefulness, numbness, hypo
or hyperthermia, elevated blood sugar,
increase heart rate, jaw clenching.
• LSD is not considered addictive drug
31. Psychological effects
• Vary greatly from person to person
• Some users cite the LSD experience
causing significant change in life pattern
• Some perceive radiant bright colors
behind the closed eye lids(imagery) and
altered sense of time & space
• This intuitive quality may play a role in
spiritual and religeous aspects of LSD
32. Clinical uses
• Alcoholism (diazepines are more better)
• Painful conditions
• Cluster headache
• End of life anxiety: study conducted in
Switzerland (2008-2011)on patients who
were in terminal illnesses and were
counting their days. They were treated
with LSD and showed promising results
33. • LSD is taken orally from 100- 500
micrograms.
• Adverse effects: hyperreflexia, nausea,
muscular weakness
• With high doses psychotic changes occur
which are relieved by haloperidol
34. Phencyclidine
• It is also called angel dust
• Inhibit the reuptake of dopamine, 5HT,
and norepinephrine
• It causes dissociative anesthesia
(insensitivity to pain without loss of
consciousness)
• Tolerance often produce with continued
use
